M.G. Brafford wrote:
>
>After suffering seven lightning strikes in the last two years, I'm >starting
>to think the "ole ground rod per tower leg" just isn't cutting >it anymore.
> 73, Mick W4YV
Mick ... I read your post with interest. I have a 145' tower with 12'
mast and 12' antenna mounted above it. I have installed PolyPhasers on
all feed lines and installed a PolyPhaser strike counter. I even
extended the leads longer than recommended which should allow me to
measure near strikes. To date (after several severe storms) I have no
recordings on the counter.
I noticed that you have done the normal grounding setup by most amateurs
but (and I might have missed it) I did not hear you say you had bonded
all tower sections together. That might be why your Indonesian friends
tower has not suffered a strike. Try bonding the tower sections to
gether at the joints. Use stainless bands and straps and use a
electrical antioxidant to treat the connections.
What is probably happening is that the joints have oxidized and thus the
tower is building a charge (capacitor effect) that is not bleed off by
the ground strap well ... until the charge builds to such a level or the
tower is struck due to the charge it holds. Grounding lowers the
potential due to static charge build up, but only if a low resistant
path is present to bleed off the charge.
I don't profess to know alot about grounding. I my self am learning but
one of our local repeaters will get very noisy (electrically) when the
joints oxidize in the joints. Bonding the sections reduces this build
up.
I hope someone will add more to this or help in any way that I might
have miss lead you. Hope this helps !!!!
Steve
KD4WIW
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TOWERS ARE BEAUTIFUL !!!!
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